An apparatus for processing a video signal and method thereof are disclosed. The present invention includes receiving the video signal, extracting discrete cosine transform information from the video signal, and performing inverse discrete cosine transform using the discrete cosine transform information, wherein the discrete cosine transfoirm information indicates a rearrangement mode of blocks in the discrete cosine transform. Accordingly, a video signal processing method of the present invention, improves efficiency of discrete cosine transform in a manner of rearranging blocks of video signal by considering a prediction mode prior to performing discrete cosine transform. The present invention enhances coding efficiency by using a row or column shifted matrix and shift information including information relevant to the row or column shifted matrix and by directly performing RRU (reduced resolution update) scheme on a discrete cosine transform/ inverse discrete cosine transform domain.